Repeating caseless tool



June 23, 1970 0. F. BUTLER 3,516,246

REPEATING CASELESS TOOL Filed 'Nov. 1, 1968 s Sheets-Sheet 1 DAV/D EBUTLER ATTORNEY INVENT OR June 23, 1970 D. F. BUTLER 3,516,246

REPEATING CASELESS TQOL Filed Nov. 1, 1968 5 Sheets-Sheet 3 FIG -4 INVENTORZ DAV/D FBUTLE/P BY uly'm ATTORNEY June 23, 1970 D. F. BUTLER 3,516,246

REPEATING GASELESS TOOL INVENTOR'.

DAVID E BUTLER ATTORNEY United States Patent 3,516,246 REPEATING CASELESS TOOL David F. Butler, Hamden, Conn., assignor to Olin Mathieson Chemical Corporation, a corporation of Virginia Filed Nov. 1, 1968, Ser. No. 785,837 Int. Cl. F01b 29/08; B25c 1/14, 1/16 U.S. Cl. fill-26.11 11 Claims ABSTRACT OF THE DISCLOSURE A power actuated tool utilizing caseless ammunition and having an ammunition magazine for automated feeding the individual caseless pellets into a firing chamber contained in the receiver of the tool.

This invention relates to a power-actuated tool for driving studs, nails, or the like, which tool utilizes caseless pelletized ammunition as the source of its operating power. The tool of this invention includes a pellet magazine for feeding individual ones of a plurality of pellets disposed therein into a firing chamber located in the bolt of the tool.

The explosively-actuated tool industry has recently turned to the use of caseless pelletized ammunition as a power source in lieu of the standard cased ammunition now widely used with power tools of this variety. The use of caseless ammunition in this field presents many advantages, the chief among which is the relative low cost of the ammunition when compared with standard cased ammunition. Another advantage attendant to the use of caseless ammunition involves the elimination of the spent casing which must be extracted after firing and often retained for reloading. Thus a power-actuated tool utilizing caseless ammunition eliminates the need of incorporating expensive extractor and ejector mechanisms in the tool, and also eliminates the bothersome necessity for the operator to collect and save the spent casings, or the safety hazard of spent cases left on the job site.

While caseless explosively-actuated tools are generally economically advantageous, the prior art tools of this type also present several disadvantages, particularly with respect to the provision of a caseless tool having incorporated therein a magazine for automatic feeding of ammunition pellets into a firing chamber. The provision of an ammunition magazine in a caseless tool presents a number of problems relating to satisfactory and safe operation of the tool. One problem attendant to the caseless tool relates to the sealing of the firing chamber when the tool is fired, and the need to protect the ammunition in the magazine from exposure to the high temperature, high pressure gases generated by firing a caseless pellet. Since the ammunition has no casing to aid in sealing the firing chamber, an adequate gas sealing mechanism must be provided in the tool itself. Furthermore, the gas sealing feature should preferably be provided with a relatively simple and economical tool design.

A second problem which presents itself in a caseless tool having an ammunition magazine relates to the transfer of the caseless pellets from the magazine to the firing chamber. Due to the elimination of the casing, the ammunition pellets often tend to be more fragile than standard cased ammunition. Thus the transfer of the caseless pellets from the magazine to the firing chamber should preferably be accomplished with a minimum of mechanical handling and a minimum of stress being imparted to the pellets. Also, since the caseless pellets lack a protective casing, they are more sensitive to heat generated by firing, and for this reason the magazine should be remotely placed with respect to the firing chamber of the tool. Obviously this latter requirement increases the "ice problem of smoothly transfering the caseless pellets from the magazine to the firing chamber.

A third problem arising with explosively actuated tools in general relates to the noise level generated by the firing of such tools. Muffling of the explosion renders the tool more desirable from the standpoint of the operator who uses the tool for extended periods of time. Yet another problem which arises in connection with all explosively actuated tools of the piston variety, relates to a simple, yet automatic means for returning the piston to its initial position after the tool is fired.

Bearing in mind all of the above-noted problems, and in particular the first two, a caseless tool featuring an ammunition magazine is still substantially more desirable from an operating standpoint than a single shot tool. By providing an ammunition magazine, the need for manually loading the caseless pellets is eliminated and thus the operating time is speeded up. Also, the operator need not carry a quantity of individual pellets around in his pocket, since a number of preloaded, easily interchangeable magazines may be used. Also the magazine provides a safe means for containing the pellets, and the magazine may be specially treated or constructed to protect the pellets against physical damage or weathering by the elements during operation.

The explosively actuated tool of this invention provides for the automatic transfer of ammunition from the magazine to the firing chamber with a minimum of physical handling, the transfer being accomplished by a simple manual manipulation of the tool. The tool includes a handle member having a barrel member movably connected thereto. A piston is slidably mounted in the barrel for movement along the axis of the barrel. A buffer means is mounted in the barrel and rigidly connected to the handle. An ammunition magazine is rigidly connected to the handle, the magazine extending parallel to the barrel. A bolt is movably mounted in the barrel for movement in a direction generally perpendicular to the axis of the barrel, the bolt combining with a portion of the barrel to define a firing chamber which is remotely spaced apart from the magazine. An actuating slide is mounted on the barrel and linking means interconnect the actuating slide and the bolt so that after the tool is fired, the initial movement of the actuating slide causes the bolt to move away from its battery position. Further movement of the actuating slide causes the barrel member to move away from the handle member and at the same time moves the bolt toward the magazine. When the bolt reaches the magazine, a caseless pellet is fed onto the bolt from the magazine. The initial portion of the return movement of the actuating slide then causes the barrel to move toward the handle, and subsequent return movement of the actuating slide causes the bolt to return to its battery position. Since the buffer means is fixed to the handle, movement of the barrel away from the handle causes the butter to bear against the piston and return the latter to its firing position. The piston then remains in its firing position as the barrel is subsequently moved back toward the handle. A further feature of the tool of this invention is the provision of a locking block actuated by the initial portion of the trigger pull, which locking block locks the bolt in its battery position during firing of the tool. After the tool is fired, the locking block is disabled, and the bolt is freed to move away from its battery position.

It is, therefore, an object of this invention to provide an explosively actuated tool for use with caseless ammunition, which tool includes an ammunition magazine remotely positioned with respect to the firing chamber of the tool.

It is a further object of this invention to provide a tool of the character described having a barrel portion 3 movably mounted on a handle portion, and having a bolt movably mounted in the barrel portion, the bolt being movable through a first direction perpendicular to the axis of the barrel, and through a second direction toward the magazine.

It is yet another object of this invention to provide a tool of the character described having a releasable locking block to lock the bolt in its battery position during the firing of the tool, the locking block being removed during the cartridge feeding actuation of the tool.

It is still another object of this invention to provide a tool of the character described wherein a tool work piston is automattically returned to its firing position during the cartridge feeding actuation of the tool after the latter has been fired.

These and other objects and advantages of this invention will become more readily apparent from the following detailed description and accompanying drawings in which:

FIG. 1 is a side elevation of a preferred embodiment of the tool of this invention;

FIG. 2 is a side sectional view of the tool of FIG. 1, showing the various components thereof as they are disposed an instant before the tool is fired;

FIG. 3 is a side sectional vie-w similar to FIG. 2, but showing the tool after the latter has been fired and a fastener has been driven into a supporting surface;

FIG. 4 is a side sectional view similar to FIGS. 2 and 3, but showing the initial phase of the movement of the actuating slide, and showing the resulting movement of the bolt out of its battery position and into alignment with the magazine; and I FIG. 5 is a side sectional view similar to FIGS. 2-4, but showing the subsequent phase of the actuation of the tool wherein the piston is returned to its firing position and the bolt is moved to a pellet pickup position.

Referring now to FIG. 1, a preferred embodiment of the tool of this invention is shown. The tool includes a handle portion 2 and a barrel portion 4 movably connected to the handle 2. The barrel 4 includes a muzzle bushing 6 which may be integral or removable, and a sound mufller 8. A tubular ammunition magazine 10 is rigidly connected to the handle 2, the magazine 10 being mounted below and parallel to the barrel 4. An actuating sleeve 12 is slidably mounted on the barrel 4, the operation of which sleeve will be set forth hereinafter in greater detail. A linking arm 14 is pivotally mounted about a pin 16 secured to the barrel 4. The forward end portion of the linking arm 14 includes a camming slot 18 in which a pin 20 secured to the actuating sleeve 12 is slidably disposed. The rearward end portion of the linking arm 14 includes a second camming slot 22 in which a pin 24 is slidably mounted. The pin 24 extends through an L-shaped slot 26 in the handle 2. It is noted that while a single linking arm 14 is shown, any type of mechanical linkage may be used without departing from the spirit of this invention.

Referring now to FIG. 2, a vertical sectional view of the tool of FIG. 1 is shown immediately prior to the firing of a fastener into a supporting surface. The fastener 28 is mounted in the muzzle bushing 6, and the latter is placed next to the supporting surface 30. Internally, the tool includes a bolt 32 which is shown in FIG. 2 in its battery position. The bolt 32 is slidably disposed in a bore 34 which extends laterally in the barrel 4 of the tool. A pair of gas sealing grooves 36 are positioned on the exterior of the bolt 32 so as to seal the bore 34 against high pressure gases developed when the tool is fired. A recess 38 is formed in the upper portion of the bolt 32 for the reception of a caseless ammunition pellet 40 of nitrocellulose, or the like. A gas passage 42 provides communication between the recess 38 and a bore 44 in the barrel in which the head portion 46 of a work piston 48 is disposed. The piston 48, which is shown in its firing position in FIG. 2, includes, anenlarged flange 50 inter- 4 posed between the head 46 and a stem 52. It is noted tha the piston 48 is slidably mounted Within the barrel 4. An annular energy-absorbing bulfer element 54, preferably of polyurethane, or the like, is positioned within the barrel 4. The buffer 54 serves to'absorb energy from engagement with the piston flange 50 in the event of a free flight shot of the tool. Furthermore, the buffer absorbs energy if a fastener is driven into a soft surface. The buffer 54 also serves to return the piston 48 from its fired position to its firing position, as will be described hereafter in greater detail. The buffer 54 is mounted in a retaining ring 56 positioned within the barrel 4 for sliding movement therein. The retaining ring 56 is rigidly secured to the magazine 10 by means of a pin 58 which extends through a slot 60 in the barrel 4.

The bolt 32 houses a firing pin 62 having a radial flange 64 disposed in an internal chamber 66 in the bolt 32. A compressible spring 6-8 is disposed in the chamber 66 and bears against the firing pin flange 64 to bias the firing pin 62 toward the ammunition pellet 40. The firing pin 62 includes a terminal flange 70 which is engaged by a Scar 72 when the firing pin 62 is cocked, as shown in FIG. 2. The bolt 32 also includes a forwardly extending camming block 74 and a rearwardly extending lug 76. The pin 24 is rigidly secured to the lug 76.

A bolt-locking block 78 is slidably mounted in a recess 80 in the handle 2 of the tool, The rear portion 82 of the bolt-locking block 78 is bifurcated to receive an extended finger portion 84 of the trigger 86. A pin 88 is secured to the block 78 and extends across the bifurcated portion 82 thereof, the pin 88 extending through a camming slot 90 in the extended portion 84 of the trigger for sliding movement therein. It is noted that the trigger is pivoted about a pin 92 and biased thereabout in a clockwise direction by a spring 94. The sear 72 is pivoted about a pin 96 and biased thereabout in a counterclockwise direction by a spring 98. A laterally extending lug 100 is mounted on the trigger 86 to bear against the sear 72 when the trigger is pulled.

The magazine 10 houses a plurality of caseless ammunltlon pellets 40, each preferably having a primer portion 41 thereon for detonation purposes. A pellet follower 102 is mounted in the magazine 10 and biased by a spring 104 to urge the pellets 40 toward the mouth 11 of the magazine. It is noted that the mouth 11 of the magazine 10 is laterally and longitudinally offset from the bolt recess 38 when the bolt is in its battery position. Thus the pellets 40 in the magazine 10 are protected from a heat and gases developed when the tool is fired. A pellet cut-off member 106 is pivotally mounted on the handle 2 about the pin 108. The cut-off 106 in-. cludes a tooth 110 which blocks the mouth 11 of the magazine 10 to prevent the pellets 40 from moving out of the magazine. A blade spring 112 bears against the cut-off 106 to urge the tooth 110 into its blocking position. I

The tool in FIG. 2 is shown after the trigger 86 has been pulled an initial amount sufficient to slide the block 78 under the bolt lug 76, but not yet far enough to disengage the sear 72 from the firing pin flange 70. It is noted that, ordinarily, the spring 94 biases the extended portion 84 of the trigger in a counter-clockwise direction to retract the block 78 into the recess 80. A pulling of the trigger 86, however, causes the slot 90 to act upon the pin 88 to slide the block 78 into its boltlocking position. Further pulling of the trigger 86 moves the pin 100 against the sear 72 and causes the latter to pivot out of engagement with the firing pin flange 70. The spring 68 then drives the firing pin 62 against the pellet primer 41 to detonate the pellet 40.

Referring now to FIG. 3, the various components of the tool are shown after the caseless pellet has been fired and the piston 48 has driven the fastener 28 into the supporting surface 30. After the piston head 46 leaves the bore 44, thecombustion gases expand into a closed chamber 111 in the mutlier 8 to deaden the sound of firing the tool. The path of the gases into the chamher 111 is denoted by arrows 114. It is noted that the piston flange 50 is driven to a point adjacent the butter 54, and it is readily apparent that the buffer 54 can absorb energy from the piston 48 in the event of a free flight shot. When the tool is fired, the high pressure gases generated act against the bolt 32 and force the bolt lug 76 tightly against the locking block 78. The trigger spring 94 is thus unable to return the trigger 86 to its original position until the pressure is reduced. When the pressure is dissipated, the trigger spring 94 returns the trigger 86 to its original position, and the block 78 is automatically slid back into the recess 80 and out of contact with the bolt lug 76.

Reference is now had to FIG. 4 regarding the preparation of the tool for another firing. After the tool is fired and the trigger 86 is returned to its original position, the actuating sleeve 12 is grasped and slid forward over the barrel 4. This movement of the actuating sleeve 12 causes the bolt 32 to move downwardly out of the bore 34 to the position shown in FIG. 4. This movement of the sleeve 12 and bolt 32 is accomplished in the manner shown most clearly by the phantom lines in FIG. I. As the sleeve 12 moves to the position 12, the pin 20 slides through the camming slot 18 on the link arm 14 and causes the latter to pivot about the pin 16 to the position 14'. This pivotal movement of the link arm 14 causes the cam slot 22 to slide over the pin 24, which is secured to the bolt lug 76, thus causing the pin 24 to move downwardly through the slot 26. It is noted that when the sleeve 12 and the link arm 14 reach the positions depicted in phantom in FIG. 1, the pins 20 and 24 have reached the ends of the respective slots 18 and 22. Thus the sleeve 12' is now rigidly connected to the barrel 4 by means of the link 14' and the pin 16. For this reason, further forward movement of the actuating sleeve 12 with respect to the handle 2 causes the barrel 4 to slide forwardly away from the handle 2.

Forward movement of the actuating sleeve 12 and the barrel 4 is continued to the point shown in FIG. 5. The forward movement of the barrel 4 causes the bolt 32 to move toward the magazine mouth 11 until the bolt recess 38 is adjacent to the magazine mouth 11, as shown in FIG. 5. As the bolt 32 moves toward the magazine mouth 11, the camming block 74 pivots the pellet cut-oif 106 against the bias of the spring 112 to move the tooth 110 out of its pellet blocking position. When the tooth 110 is moved free, the bolt recess 38 is adjacent to the magazine mouth 11, and a pellet 40 is fed from the magazine into the recess 38.

The further forward movement of the sleeve 12 and barrel 4 also returns the piston 48 to its firing position in the following manner. As previously noted, the butter retaining ring 56 and the butter 54 are rigidly connected to the magazine 10 by means of a pin 58 which extends through a slot 60 in the barrel 4. Since the magazine 10 is rigidly connected to the handle 2, the buffer 54 is immobile with respect to the handle 2. As the barrel 4 is moved forward, the barrel bore 44 moves toward the piston head 46, the piston 48 being held in place by the buffer 54. Thus the piston head 46 is moved into the bore 44, as shown in FIG. 5. To ready the tool for firing, the sleeve 12 is merely moved back toward the handle 2 to first move the barrel 4 and bolt 32 back toward the handle 2, and secondly move the bolt 32 back up into the bore 34. The piston head 46 is frictionally retained in the barrel bore 44 so that the return movement of the barrel 4 causes the piston to return to its firing position. It is noted that before the bolt 32 is moved back into its battery position, the sear 72 engages the firing pin flange 70 and the firing pin 62 is cocked during the movement of the bolt toward its battery position.

It is thus readily apparent that the tool of this invention provides for automatic feeding of caseless ammunition from a magazine to a bolt, while maintaining the magazine in a position remote from the firing chamber area of the tool. The tool also provides for simple actuation which serves the dual purposes of reloading and returning the piston to its firing position after driving a fastener. A relatively simple, and yet rugged construction is provided to assure long life and dependable operation.

Since many changes and variations of the disclosed embodiment of the invention may be made without departing from the inventive concept, it is not intended to limit the invention otherwise than as required by the appended claims.

What is claimed is:

1. An explosively actuated tool utilizing caseless ammunition pellets, said tool comprising:

(a) a handle portion;

(b) a barrel portion movably mounted on said handle portion, said barrel portion including at least two bores extending perpendicularly to each other;

(c) a bolt mounted in a first one of said barrel bores and movable therein into a battery position to seal said first barrel bore against passage of combustion gases, said bolt having a recess adapted to receive an ammunition pellet;

((1) piston means mounted in the other of said barrel bores, said piston means being movable therein between a firing position and a fired position;

(e) magazine means rigidly secured to said handle portion said magazine means being adapted to receive a plurality of caseless ammunition pellets, and said magazine means having a feed mouth positioned remotely from the battery position of said bolt; and

(f) actuating means movably mounted on said tool and connected to said bolt, said actuating means being operable to move said bolt from its battery position to a position adjacent said magazine feed mouth and return.

2. The tool of claim 1, further comprising blocking means mounted in said handle portion, said blocking means being operative to selectively lock said bolt in its battery position.

3. The tool of claim 2, further comprising trigger means connected to said blocking means, said trigger means being operative to move said blocking means into and out of a bolt-locking position.

4. The tool of claim 1, further comprising buffer means slidably mounted in the other of said barrel bores, said bufier means being operative to absorb free shot energy from said piston, and said buffer means further being operative to return said piston from its fired position to its firing position upon movement of said barrel portion away from said handle portion.

5. The tool of claim 1, further comprising pellet cutoff means adjacent said magazine feed end to retain ammunition pellets in said magazine, said pellet cut-off means being disabled by contact with said bolt when the latter is adjacent said magazine mouth to permit an ammunit on pellet to be fed into said bolt recess.

6. The tool of claim 1, further comprising sound muflle means.

7. An explosively actuated tool utilizing caseless ammunition pellets, said tool comprising:

(a) a handle portion;

(b) a barrel portion movably mounted on said handle portion;

(c) a bolt mounted in said barrel in gas sealing engagement therewith, said bolt being movable into a battery position within said barrel portion, and said bolt having a recess adapted to receive an ammunition pellet;

(d) piston means mounted in said barrel for movement between a firing position and a fired position;

(e) an ammunition magazine rigidly connected to said handle portion, said magazine being laterally offset from said piston means, and said magazine having a feed mouth laterally offset from said bolt;

(f) pellet cut-off means adjacent said magazine feed mouth, said out ofi? means being operative to block movement of pellets through said feed mouth;

(g) buifer means movably mounted in said barrel portion and rigidly connected to said handle portion, said buffer means being operative to engage said piston means when the latter is in its fired position;

(h) actuating means movably mounted on said barrel portion and connected to said bolt whereby movement of said actuating means causes said bolt to move away from its battery position to a position wherein said bolt recess is aligned with said magazine mouth, and whereby further movement of said actuating means causes said barrel portion to move away from said handle portion to move said bolt recess toward said magazine mouth; and

(i) means on said bolt operative to engage said pellet cutoif means when said bolt recess is adjacent said magazine mouth so that said cut-off means is disabled from blocking movement of a pellet into said bolt recess.

8. The tool of claim 7, wherein actuating means includes linking means pivotally mounted on said barrel portion and drivingly connected to said bolt.

9. The tool of claim 7, further comprising blocking means mounted in said handle portion, said blocking means selectively engaging said bolt when the latter is in its battery position to lock said bolt in its battery position when said tool is fired.

10. The tool of claim 9, further comprising trigger means to fire said tool, said trigger means being connected to said blocking means to move the latter into and out of its bolt-locking position.

11. The tool of claim 7, further comprising noise mufilin-g means comprising a chamber communicating with said barrel portion.

References Cited UNITED STATES PATENTS 3,330,108 7/1967 Kvavle et al. 60-26.1

WENDELL E. BURNS, Primary Examiner US. Cl. 227-10 

